Stripper head system and method of use

Abstract

A stripper head assembly for holding back pressure while stripping a work-string from pressurized well environment is disclosed. The stripper head assembly comprises a stripper head, a stripper insert, a stripper rubber, one or more retention bushing assemblies, one or more retention pins, and one or more retention apertures. The stripper head comprises an outer portion of the stripper head assembly. The stripper head comprises, from top to bottom, a top portion, a body portion, a lower neck portion and a flange base. A portion of the stripper insert fits within a portion of the stripper rubber. A portion of the stripper rubber fits within a portion of the stripper head.

The invention claimed is: 
     
       1. A stripper head assembly for holding back pressure while stripping a work-string in and out of a pressurized well environment, wherein:
 said stripper head assembly comprises a stripper head, a stripper insert, a stripper rubber, one or more retention bushing assemblies, one or more retention pins, and one or more retention apertures; 
 said stripper head comprises an outer portion of said stripper head assembly; 
 said stripper head comprises, from top to bottom, a top portion, a body portion, a lower neck portion and a flange base; 
 a portion of said stripper insert fits within a portion of said stripper rubber; 
 a portion of said stripper rubber fits within a portion of said stripper head; 
 a portion of one or more bolts attach said flange base of said stripper head assembly equipment attached to a well head at said pressurized well environment, such as a blow-out preventer; 
 said stripper rubber comprises a rubber material; 
 each among said one or more retention bushing assemblies are configured to seal a retention pin cavity within said one or more retention apertures and around a portion of said one or more retention pins; 
 said one or more retention pins are configured to hold said stripper head assembly in place relative to said work-string; 
 each among said one or more retention bushing assemblies comprises one or more retention bushings, one or more grease ports, and a bleeder hole; 
 said bleeder hole allows a portion of a lubricant within said retention pin cavity to selectively escape at a given pressure; 
 said one or more grease ports are configured to selectively receive said lubricant into said retention pin cavity; 
 each among said one or more retention bushings comprises a ring comprising an interior O-ring groove, an exterior O-ring groove, a center aperture, a grease aperture, and said bleeder hole; 
 said interior O-ring groove and said exterior O-ring groove is configured to each be configured to contain a second O-ring and a third O-ring; 
 said second O-ring is configured to seat into said exterior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said stripper head; and 
 said third O-ring is configured to seat into said interior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said one or more retention pins. 
 
     
     
       2. The stripper head assembly of  claim 1 , wherein:
 each among said one or more retention bushings comprises a ring comprising said interior O-ring groove, said exterior O-ring groove, said center aperture, a grease aperture, and a bleeder hole; 
 said interior O-ring groove and said exterior O-ring groove is configured to each be configured to contain said second O-ring and said third O-ring; 
 said second O-ring is configured to seat into said exterior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said stripper head; and 
 Said third O-ring is configured to seat into said interior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said one or more retention pins. 
 
     
     
       3. The stripper head assembly of  claim 2 , wherein:
 each among said one or more retention apertures are configured to further comprise an O-ring groove which is configured to contain a first O-ring configured to seal a portion of said one or more retention pins with said one or more retention apertures. 
 
     
     
       4. A stripper head assembly for holding back pressure while stripping a work-string in and out of a pressurized well environment, wherein:
 said stripper head assembly comprises a stripper head, a stripper insert, a stripper rubber, one or more retention bushing assemblies, one or more retention pins, and one or more retention apertures; 
 said stripper head comprises an outer portion of said stripper head assembly; 
 said stripper head comprises, from top to bottom, a top portion, a body portion, a lower neck portion and a flange base; 
 a portion of said stripper insert fits within a portion of said stripper rubber; 
 a portion of said stripper rubber fits within a portion of said stripper head; 
 a portion of one or more bolts attach said flange base of said stripper head assembly equipment attached to a well head at said pressurized well environment, such as a blow-out preventer; 
 said stripper rubber comprises a rubber material; 
 each among said one or more retention bushing assemblies are configured to seal a retention pin cavity within said one or more retention apertures and around a portion of said one or more retention pins; 
 said one or more retention pins are configured to hold said stripper head assembly in place relative to said work-string; 
 each among said one or more retention bushing assemblies comprises one or more retention bushings, one or more grease ports, and a bleeder hole; 
 said bleeder hole allows a portion of a lubricant within said retention pin cavity to selectively escape at a given pressure; and 
 said one or more grease ports are configured to selectively receive said lubricant into said retention pin cavity. 
 
     
     
       5. The stripper head assembly of  claim 4 , wherein:
 each among said one or more retention bushings comprises a ring comprising an interior O-ring groove, an exterior O-ring groove, a center aperture, a grease aperture, and said bleeder hole; 
 said interior O-ring groove and said exterior O-ring groove is configured to each be configured to contain a second O-ring and a third O-ring; 
 said second O-ring is configured to seat into said exterior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said stripper head; and 
 said third O-ring is configured to seat into said interior O-ring groove and create a seal between said one or more retention bushing assemblies and a portion of said one or more retention pins. 
 
     
     
       6. The stripper head assembly of  claim 5 , wherein:
 each among said one or more retention apertures are configured to further comprise an O-ring groove which is configured to contain a first O-ring configured to seal a portion of said one or more retention pins with said one or more retention apertures. 
 
     
     
       7. The stripper head assembly of  claim 4 , wherein:
 said one or more retention apertures are configured to further comprise a snap ring groove which is configured to hold said one or more retention bushing assemblies within said one or more retention apertures. 
 
     
     
       8. The stripper head assembly of  claim 4 , wherein:
 each among said one or more retention bushing assemblies comprise said one or more grease ports; 
 each said one or more retention apertures comprise said retention pin cavity; 
 said retention pin cavity comprises a cavity between portions of said one or more retention apertures and said one or more retention pins; 
 said one or more grease ports are configured to receive said lubricant; 
 said lubricant is inserted into said retention pin cavity through said one or more grease ports; and 
 said lubricant is configured to lubricate parts of said one or more retention apertures and said one or more retention pins are protected from friction and heat. 
 
     
     
       9. The stripper head assembly of  claim 4 , wherein:
 said stripper rubber comprises a form fitting element for use within said stripper head assembly; 
 said stripper rubber comprises a lower aperture and an upper aperture at either end of a center aperture; 
 said stripper rubber comprises an inner surface around an interior space comprising said center aperture; 
 said stripper rubber comprises a collar portion attaching to an upper mid portion; 
 said upper mid portion comprises a substantially cylindrical hollow element for selectively being held within an inner sidewall of said stripper insert; 
 a lower portions of said upper mid portion extend down toward said lower aperture and forming a multi-stage loading zones; and 
 said multi-stage loading zones are configured to directing pressures to enhance the seal of said stripper rubber within said stripper head assembly. 
 
     
     
       10. The stripper head assembly of  claim 4 , wherein:
 said stripper head assembly comprises several components which selectively nest within one another; wherein, 
 a portion of said stripper insert is configured to fit within a portion of said stripper rubber; 
 a portion of said stripper rubber is configured to fit within a portion of said stripper head; 
 a portion of said one or more bolts are configured to attach to a portion of said stripper head; 
 a portion of said one or more retention bushing assemblies fit within a portion of said stripper head; and 
 a portion of said one or more retention pins fit within a portion of said one or more retention bushing assemblies. 
 
     
     
       11. The stripper head assembly of  claim 4 , wherein:
 a side surface of said stripper head comprises one or more flanged outlets; and 
 said one or more flanged outlets are used for pressure equalization and bleed-off. 
 
     
     
       12. The stripper head assembly of claim/wherein:
 said stripper insert is molded into said stripper rubber and bonded together through an injected rubber molding process. 
 
     
     
       13. The stripper head assembly of  claim 4 , wherein:
 said stripper insert comprises an insert upper ring, one or more stalks, and an insert lower ring; 
 said stripper insert is configured to fit within a portion of said stripper rubber; 
 wherein, said one or more stalks and said insert lower ring is configured to nest within said stripper rubber; 
 said one or more stalks comprises cylindrical elements expending down from a lower portion of said insert upper ring; 
 said insert lower ring comprises a portion of said insert upper ring having been cut away; and 
 said insert lower ring comprises a substantially circular element adapted to prevent movement of said stripper insert relative to said stripper rubber once attached thereto. 
 
     
     
       14. The stripper head assembly of  claim 13 , wherein:
 said insert upper ring comprises an anti-rotation tab adapted to prevent rotation of said stripper insert with a portion of said one or more retention pins inserted into a portion of said insert upper ring; 
 said anti-rotation tab is inserted into a portion of an indention to block off a portion of said indention; 
 a plurality of said anti-rotation tab is used, as needed; and 
 said anti-rotation tab is welded into a portion of said indention. 
 
     
     
       15. The stripper head assembly of  claim 4 , wherein:
 said stripper rubber comprises a form fitting element for use within said stripper head assembly being defined with said lower aperture and said upper aperture at either end of said center aperture; 
 said inner surface around an interior space comprising said center aperture; 
 said collar portion attaching to said upper mid portion; 
 said upper mid portion comprising a substantially cylindrical hollow element for selectively being held within said inner sidewall of said stripper insert; 
 a lubrication groove cut into a portion of said lower portions; 
 a shoulder extending out from said upper mid portion to form a lower mid portion; 
 a seal lip comprising an outwardly extending material comprising a pressure trap between said lower mid portion and said lower portions; 
 said lower portions extending down toward said lower aperture and forming said multi-stage loading zones; and 
 said multi-stage loading zones configured to directing pressures so as to enhance the seal of said stripper rubber within said stripper head assembly. 
 
     
     
       16. The stripper head assembly of  claim 15 , wherein:
 said pressure trap comprises an internal taper; 
 said internal taper is configured to create an early seal with an internal surface of said stripper head; 
 n this manner, said pressure trap is self-energized to press said seal lip into said internal surface; 
 said seal lip is configured to have enough initial contact to create the initial seal which is configured to then hold; 
 self-energized is configured to mean that said stripper rubber need not be compressed or squeezed at installation to create the initial seal, rather it need only be inserted into said stripper head; and 
 said internal taper of said pressure trap is configured to tighten under pressure as said pressure trap will enhance a seal with said internal surface under pressure. 
 
     
     
       17. The stripper head assembly of  claim 16 , wherein:
 said internal taper of said pressure trap is configured to tighten under pressure as said pressure trap will enhance a seal with said internal surface under pressure; 
 said multi-stage loading zones are configured to build its hold on a tubing within said stripper head assembly by increasing the cross-section thickness of said stripper rubber as said multi-stage loading zones increase from a first stage to a second stage to a third stage to a fourth stage; 
 likewise, the relative angle of said fourth stage and said second stage convert pressure into inward force on tubing; and 
 pressure on said fourth stage is configured to assert pressure on said insert lower ring and said one or more stalks within said stripper rubber. 
 
     
     
       18. The stripper head assembly of  claim 4 , wherein:
 said one or more retention pins are configured to selectively slide into said one or more retention apertures and selectively attach thereto by screwing an external threading of said one or more retention pins into an internal threading of said one or more retention apertures. 
 
     
     
       19. A stripper head assembly for holding back pressure while stripping a work-string in and out of a pressurized well environment, wherein:
 said stripper head assembly comprises a stripper head, a stripper insert, a stripper rubber, one or more retention bushing assemblies, one or more retention pins, and one or more retention apertures; 
 said stripper head comprises an outer portion of said stripper head assembly; 
 said stripper head comprises, from top to bottom, a top portion, a body portion, a lower neck portion and a flange base; 
 a portion of said stripper insert fits within a portion of said stripper rubber; 
 a portion of said stripper rubber fits within a portion of said stripper head; 
 a portion of one or more bolts attach said flange base of said stripper head assembly equipment attached to a well head at said pressurized well environment, such as a blow-out preventer; 
 said stripper rubber comprises a rubber material; 
 each among said one or more retention bushing assemblies are configured to seal a retention pin cavity within said one or more retention apertures and around a portion of said one or more retention pins; 
 each among said one or more retention bushing assemblies comprise said one or more grease ports; 
 each said one or more retention apertures comprise said retention pin cavity; 
 said retention pin cavity comprises a cavity between portions of said one or more retention apertures and said one or more retention pins; 
 said one or more grease ports are configured to receive said lubricant; 
 said lubricant is inserted into said retention pin cavity through said one or more grease ports; and 
 said lubricant is configured to lubricate parts of said one or more retention apertures and said one or more retention pins are protected from friction and heat. 
 
     
     
       20. A stripper head assembly for holding back pressure while stripping a work-string in and out of a pressurized well environment, wherein:
 said stripper head assembly comprises a stripper head, a stripper insert, a stripper rubber, one or more retention bushing assemblies, one or more retention pins, and one or more retention apertures; 
 said stripper head comprises an outer portion of said stripper head assembly; 
 said stripper head comprises, from top to bottom, a top portion, a body portion, a lower neck portion and a flange base; 
 a portion of said stripper insert fits within a portion of said stripper rubber; 
 a portion of said stripper rubber fits within a portion of said stripper head; 
 a portion of one or more bolts attach said flange base of said stripper head assembly equipment attached to a well head at said pressurized well environment, such as a blow-out preventer; 
 said stripper rubber comprises a rubber material; 
 each among said one or more retention bushing assemblies are configured to seal a retention pin cavity within said one or more retention apertures and around a portion of said one or more retention pins; 
 said stripper rubber comprises a form fitting element for use within said stripper head assembly; 
 said stripper rubber comprises a lower aperture and an upper aperture at either end of a center aperture; 
 said stripper rubber comprises an inner surface around an interior space comprising said center aperture; 
 said stripper rubber comprises a collar portion attaching to an upper mid portion; 
 said upper mid portion comprises a substantially cylindrical hollow element for selectively being held within an inner sidewall of said stripper insert; 
 a lower portions of said upper mid portion extend down toward said lower aperture and forming a multi-stage loading zones; and 
 said multi-stage loading zones are configured to directing pressures to enhance the seal of said stripper rubber within said stripper head assembly.